Analyses of biological and chemical specimens may be performed conventionally using large, expensive laboratory equipment requiring skilled scientists trained to operate the equipment and interpret the results. In some cases, detection and analysis of biological samples may be performed using biological assays (“bioassays”). Bioassays are conventionally performed in bulk such that a large amount of a particular type of sample is necessary for detection and quantitation.
Some bioassays are performed by tagging samples with luminescent tags that emit light of a particular wavelength. The tags are illuminated with an excitation light source to cause luminescence, and the luminescent light is detected with a photodetector to quantify the amount of luminescent light emitted by the tags. Bioassays using luminescent tags conventionally involve expensive laser light sources to illuminate samples and complicated, bulky luminescent detection optics and electronics to collect the luminescence from the illuminated samples.
Because conventional analytical equipment is typically expensive and requires a skilled operator, specimens to be analyzed may need to be sent to an on-site or off-site facility for processing. This can introduce appreciable delay and cost associated with even routine analysis of a specimen. For example, a patient may have to wait several days and schedule a return visit to a doctor's office to learn about the results of a laboratory test on a specimen provided by the patient.